US3876426A - Sensitizing a granular dispersion of a n-vinyl compound and an organohalogeno compound by heat - Google Patents

Sensitizing a granular dispersion of a n-vinyl compound and an organohalogeno compound by heat Download PDF

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US3876426A
US3876426A US265887A US26588772A US3876426A US 3876426 A US3876426 A US 3876426A US 265887 A US265887 A US 265887A US 26588772 A US26588772 A US 26588772A US 3876426 A US3876426 A US 3876426A
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compound
dyes
group
organohalogeno
recording material
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US265887A
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Hiroshi Yamashita
Nobuyoshi Sekikawa
Hisatake Ono
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Fujifilm Holdings Corp
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Fuji Photo Film Co Ltd
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/675—Compositions containing polyhalogenated compounds as photosensitive substances

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  • ABSTRACT The sensitivity of a recording material having dispersed in a hydrophilic binder the fine particles of an organohalogeno compound capable of forming free radicals containing halogen atoms and halogen ions on light exposure and an N-vinyl compound is improved remarkably by heating the recording material, prior to the image exposure, from 35 to 250C.
  • the instant invention relates generally to a novel process for sensitizing a recording material capable of recording images thereon due to the action of radiation. More particularly, the invention relates to a novel sensitizing process in forming images on a recording material mainly comprising finely dispersed particular of a N-vinyl compound and an organohalogeno compound in a water-soluble binder.
  • the light-sensitive materials in which a light-sensitive composition is dispersed in a hydrophilic binder in the fine droplet form are disclosed in the specifications of US. Pat. Nos. 3,476,562 and 3,503,745.
  • the latter patent relates to the sensitization of the light-sensitive material by incorporating therein a dye or a dye base.
  • the sensitizations of such light-sensitive materials have hitherto been made by the use of a dye or a dye base or the incorporation of a polycyclic aromatic hydrocarbon, ferrocene. a hydrazone compound, an anthraquinone derivative, etc.
  • An object of this invention is to provide a novel sensitizing process using a physical method different from the conventional methods employing chemical sensitizations.
  • the process of this invention comprises sensitizing a recording material comprising an organohalogeno compound capable of forming free radical containing halogens and halogen ions due to the action of radiation, an N-vinyl compound dispersed discontinuously in a hhydrophilic binder as fine particles for forming an image on exposure to radiation by heating the recording material overall prior to the exposure to radiation forming the image.
  • a light activator, a sensitizer, a stabilizer and an enhancer can also be present.
  • FIGS. 1, 2 and 3 of the accompanying drawings show the photographic characteristic curves obtained when the recording material used in this invention is subjected to the sensitizing process of this invention prior to the formation of an image in comparison with image formation in accordance with a conventional process.
  • the recording material used in this invention is prepared by dispersing discontinuously as fine particles in a hydrophilic binder an organohalogeno compound and an N-vinyl compound, and if desired, together with other components such as an activator, a sensitizer, a stabilizer, and an enhancer.
  • Suitable organohalogeno compounds to be employed in the invention are those compounds represented by the general formulas:
  • R is a hydrogen atom, a halogen atom, an aryl group, an alkyl group, an aralkyl group or an aroyl group;
  • X is a chlorine atom, a bromine atom or a iodine atom.
  • R is a hydrogen atom, a chlorine atom, a bromine atom, a iodine atom, a nitro group. an alkyl group, an alkoxyl group;
  • R., R and R each are a hydrogen atom, a chlorine atom or a bromine atom, with at least one of R,, R. and R being a halogen atom.
  • organohalogeno containing compounds within the above general formula as well as other suitable compounds which are suitable are materials such as carbon tetrachloride, hexabromoethane, pentabromoethane chloranil, bromanil, tetrachlorotetrahydronaphthalene, tetraiodomethane, iodoform, bromoform, trichlorobromomethane, tribromoethano], tribromoacetic acid, hexachloroethane, pphenylphenacyl bromide, tetrabromo-o-cresol, tetrabromophenolphthalein, hexabromobenzene, hexachlo robenzene, iodobenzene, carbon tetrabromide, tri bromoacetophenone, p-nitrotribromacetophenone, pbromotribromoacetophenone, tribrom
  • Suitable N-vinyl compounds which can be used in this invention are the compounds having the following structural formulas;
  • Nvinyl compounds having the above skeletal structures can be suitably used in this invention
  • Suitable specific examples of the N-vinyl compounds are N-vinylcarbazole and N-vinyl-carbazole which may contain substituents on the carbazole ring, e.g., alkyl groups having from 1 to 5 carbon atoms, halogen atoms, hydroxyl groups, alkoxy] groups having from 1 to 5 carbon atoms and nitro groups.
  • the above two components are the fundamental components of the light-sensitive composition used in this invention but the light-sensitive composition may also contain such other components as an activator, a sensitizer, a stabilizer, an enhancer, etc.
  • activator is intended to cover a compound which forms a free radical or ions due to the action of light and there are, for example, the quinones, inorganic halogen compounds, bishexaaryl imidazoles, disulfides, etc., for example, lead bromide, lead iodide, hexa-aryl-bi-imidazoles which may be substituted with an alkyl group or a halogen atom.
  • a sensitizer is a compound which sensitizes the coloring reaction and the polymerization reaction and specific examples of such compounds are the anthraquinones, the metallocenes, the hydrazones, the aromatic amine N-oxides, and further photographic spectral sensitizing dye materials being in a dye form or a dye base form such as the azo dyes, diphenylmethane dyes, triphenylmethane dyes, anthraquinone dyes, methine dyes, polymethine dyes, acridine dyes, azine dyes, thiazine dyes, oxazine dyes, styryl dyes, cyanine dyes, carbocyanine dyes, merocyanine dyes, xanthene dyes or their dye bases.
  • a stabilizer is a material having the action ofimproving the shelf life of the recording materials.
  • Suitable stabilizers are, for example, hydroquinone, resorcin, catechol, and their derivatives, amides, thiourea and their derivatives, for example, amides having the general formula wherein R R and R are each a hydrogen atom, an alkyl group, an aryl group or an aralkyl group.
  • suitable amides are formamide, N, N-dimethylformamide, N, N-dimethylacetoamide, and the like.
  • hydrophilic high molecular weight compounds can be used as the binder for these components. Typical ex amples of these hydrophilic high molecular weight compounds are gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, casein, starch, carboxymethyl cellulose. gum arabic, hydroxymethyl cellulose, etc.
  • the support there are illustrated paper sheets, glass sheets. plastic films, and metallic sheets.
  • the components such as the N-vinyl compound and the organohalogeno compound are hydrophobic compounds and when they are dispersed in the hydrophilic high molecular weight compound, they are believed to be distributed discontinuously in the continuous phase of the hydrophilic high molecular weight compound in the form of fine particles of about 0.1 to microns.
  • the recording material is exposed to ultraviolet rays or visible rays in compliance with an image and then, if necessary, heated to provide a colored image.
  • the recording material is image-wise exposed to ultraviolet rays or visible rays to cause the polymerization reaction and then the entire surface of the recording material is exposed to ultraviolet rays or visible rays followed, if necessary, by heating to color the unpolymerized portion, whereby a positive image is obtained.
  • images can be recorded using high energy radiations such as electron beams. X-rays. gamma rays, etc., in addition to ultraviolet rays and visible rays. Also, the recording material is suitable for recording images using the irradiation of a laser.
  • the sensitivity of such a kind of re cording material can be increased by using a sensitizer but the inventors have discovered that the sensitivity of the recording material can also be increased physically in addition to chemically. That is to say, when the recording material is heated just before use, the subsequent photo-reaction is greatly accelerated.
  • the instant invention provides a novel sensitization process in conducting image formation using the above described recording material. That is, according to the sensitization process of this invention the entire surface of the recording material is heated prior to the use of the recording material. By conducting such a pre-heating operation, the sensitivity of the recording material can be increased to 2 to 20 times that of the original one.
  • the effects of the change in gamma, the increase of image density, etc. can be obtained in addition to the increase in sen- -sitivity.
  • the phenomenon obtained by pre-heating is not completely understood, it may be explained as follows. For the sake of simplicity it is assumed that only the two components (a) and (b) are dispersed as fine particles. In such a case, it is considered that one or both of the compositions (a) and (b) is activated by the pre-heating and then becomes more reactive when it is irradiated with radiation. Also, when there is a physiochemical co-action between the component (a) and the component (b) and the lowering of melting point occurs or when the melting point of either of the components (a) and (b) is comparatively low, it is believed that the fine particles of them are melted by the heating and the reaction readily proceeds when they are exposed to radiation. When the fine particles are easily melted, the pre-heating effect is particularly remarkable.
  • the recording material may be heated using a heating plate, heating rollers, an air heating bath, an infrared radiation source, a microwave heating using a commercially available microwave oven, or a hair dryer.
  • a heating plate or a heating roller is particularly preferred and the heating temperature can range from about 35 to 250C, preferably from about 60 to IC.
  • Such a pre-heating effect is particularly remarkable in the system in which the fine particles are discontinuously dispersed although it is possible in principle in the system wherein the components are dispersed in molecular state.
  • FIG. 1 is the characteristic curves showing the relationship between the logarithmic value (relative value) of the exposure amount E of the first exposure causing the polymerization reaction and the photographic reflection density.
  • Curve 1 in FIG. 1 is the characteristic curve obtained when the recording material was subjected to a white light exposure (first exposure), a red exposure (second exposure), and mercury lamp exposure (third exposure) without employing the pre-heating operation.
  • Curve 2 is the characteristic curve obtained when the recording material was subjected to the first exposure, the second ex' posure, and the third exposure after it was pre-heated for 10 seconds at l50C. As is clear from the curves, by heating the recording material prior to the first exposure, the sensitivity thereof to the first exposure could be increased to 7.4 times the original sensitivity.
  • FIG. 2 shows the pre-heating effect on the second exposure. That is to say, the graph of the figure shows the relationship between the logarithmic value of the exposure amount in the second exposure and the photographic reflection density.
  • the recording material was sensitized by the pre-heating (Curve 2) to about 7.l times that of the non-pre-heated case (Curve 1
  • FIG. 3 shows the pre-heating effect to the response of a negative type recording material which had been dye-sensitized. That is to say, the graph of FIG. 3 shows the relationship between the logarithmic value of the exposure amount in the first exposure and the photographic reflection density.
  • Curve l is the characteristic curve obtained by subjecting the recording material to a white light exposure (first exposure), a red exposure (second exposure), and heating and Curve 2 is the characteristic curve obtained by subjecting the recording material, after the recording material was heated overall for 30 seconds to l00C, to the first exposure. the second exposure, and heating.
  • the sensitivity of the recording material was increased to 7.8 times by the pre-heating operation.
  • the recording materials were prepared and processed under a red safety lamp for photography or a safety lamp for panchromatic film.
  • EXAMPLE 1 A mixture of 25 ml of a l6% aqueous gelatin solution and 2.5 g of N-vinylcarbazole was stirred vigorously for 2 minutes at 70C in a homogenizer (made by Tokushu Kika Kogyo K. K.) to disperse the N-vinylcarbazole in the gelatin as tine particles. Then, 1.5 g of carbon tetrabromide and 0.5 of hexachloroethane were added to the dispersion followed by dispersion. The dispersion was applied to a baryta-coated paper and dried.
  • a homogenizer made by Tokushu Kika Kogyo K. K.
  • the recording material thus prepared was first heated for seconds to l30C, exposed, then, through a photographic positive image to a photographic lamp of 300 watts at a distance of cm from the lamp for l.5 seconds, exposed overall to a super high pressure mercury lamp of 250 watts at a distance of 35 cm from the lamp for one second, and further heated overall for 3 seconds to l00C, whereby a dark blue positive image was obtained.
  • the same procedures were followed without employing the pre-heating operationv In the comparison case. the recording material was. first.
  • the exposure time for the first exposure was about one-seventh of that in the comparison case and also a better image was obtained than the latter case.
  • Qulnoline (sensitizer) The mixture of the above composition was dispersed by emulsification in 50 ml ofa 15% aqueous gelatin solution and by using the dispersion thus prepared. a recording material was produced.
  • FIG. 1 shows the pre-heating effect to the first exposure.
  • Curve 1 in the figure is the characteristic curve of the recording material when it was subjected to the three-stage exposures without being subjected to the pre-heating operation and Curve 2 is the characteristic curve when the recording material was pre-heated for l seconds to l50C prior to the exposure treatments.
  • the sensitivity was evaluated using the reciprocal of the exposure amount giving a density of (maximum density l the sensitivity was increased to 7.4 times. Also. as is shown in FIG. 1 the minimum density was lowered and the formation of fog was reduced.
  • FIG. 2 shows the pre-heating effect to the second exposure.
  • Curve 1 is the characteristic curve of the re cording material when it was not preheated prior to the exposure treatments and Curve 2 is the characteristic curve when the recording material was preheated.
  • the sensitivity was increased to 7.l times by the preheating operation.
  • the sensitivity was evaluated using the reciprocal of the exposure amount giving a density of (fog density U.l the sensitivity was increased to about 8 times by the pre-heating. Also. as is shown in FIG. 3. the D,,,,,, (maximum density) increased to more than twice with the pre-heating operation and the gamma increased. Moreover. by the pre-heating operation. the color tone of image was improved to provide a blue image having good light fastness.
  • a method for forming an image on a dried recording material having on a support an N-vinyl compound and an organohalogeno compound forming free radical containing halogens and halogen ions on irradiation dispersed discontinuously as fine particles thereof in a hydrophilic binder which comprises sensitizing said material to irradiation prior to image-wise exposure by heating said dried material overall to a temperature ranging from about 60C. to 250C. for a period oftime sufficient to increase the sensitivity thereof to imageirradiation from 2 to 20 times, and imagewise exposing said material to irradiation, wherein said N-viny] compound and said organohalogeno compound are fine particles having a size of from about 0.] to 20 microns.
  • said recording material additionally contains at least one of an activator, a sensitizer, a stabilizer and an enhancer.
  • organo halogeno compound is a compound represented by the following general formulas:
  • R is a hydrogen atom. a halogen atom. an aryl group. an alkyl group, an aralkyl group or an aroyl group;
  • X is a chlorine atom, a bromine atom or a iodine atom l 1
  • A-(yJ-R wherein R is a hydrogen atom, a chlorine atom. a bromine atom, a iodine atom. a nitro group. an alkyl group. an alkoxyl group;
  • R R and R each are a hydrogen atom. a chlorine atom or a bromine atom, with at least one of R R and R being a halogen atom (III) wherein Q is a substituted or unsubstituted heterocyclic compound.
  • R R and R each are a hydrogen atom. a chlorine atom or a bromine atom. with at least one of R R and R being a halogen atom.
  • R is a hydrogen atom, a halogen atom, an aryl group, an alkyl group, an aralkyl group or an aroyl group
  • X is a chlorine atom, a bromine atom or a iodine atom wherein R is a hydrogen atom, chlorine atom, a bromine atom, a iodine atom, a nitro group, an alkyl group, an alkoxyl group,
  • R R and R each are a hydrogen atom, a chlorine atom or a bromine atom, with at least one of R R and R being a halogen atom l (III) wherein Q is a substituted or unsubstituted heterocyclic compound, R,, R and R each are a hydrogen atom, a chlorine atom or a bromine atom, with at least one of R,, R and R being a halogen atom.
  • said or gano halogeno containing compound is carbon tetrachloride, hexabromoethane, pentabromoethane, chloranil, bromanil, tetrachlorotetrahydronaphthalene, tetraiodomethane, iodoform, bromoform, trichlorobromomethane, tribromoethanol, tribromoacetic acid, hexachloroethane, p-phenylphenacyl bromide, tetrabromo-o-cresol, tetrabromophenolphthalein, hexabromobenzene, hexachlorobenzene, iodobenzene, carbon tetrabromide, tribromoacetophenone, pnitrotribromoacetophenone, pbromotribromoacetophenone, tribromophenylsulfone, or
  • N vinyl compound is N-vinyl-carbazole or a derivative thereof.
  • N- vinyl compound is N-vinyl-carbazole or a derivative thereof.
  • organohalogeno compound is carbon tetrabromide, hexabromoethane, iodoform, tribromoacetophenone, or tribromophenylsulfone.
  • organohalogeno compound is carbon tetrabromide, hexabromoethane, iodoform, tribromoacetophenone, or tribromophenylsulfone.
  • said sensitizer is a member selected from the group consisting of the anthraquinones, the metallocene's, the hydrazones, the aromatic amine N-oxides, and the spectral sensitizing dye materials selected from the group consisting of the azo dyes, triphenylmethane dyes, anthraquinone dyes, methine dyes, polymethine dyes, acrydine dyes, azine dyes, thiazine dyes, oxazine dyes, styryl dyes, cyanine dyes, carbocyanine dyes, merocyanine dyes, xanthene dyes in their dye form and their dye base form.
  • sensitizer is a dye in its dye form or its dye base form.
  • sensitizer is a styryl dye or a styryl dye base.
  • sensitizer is 4(p-dimethylamino)styrylquinoline.
  • said stabilizer is a compound selected from the group consisting of hydroquinone, resorcin, catechol, and their derivatives, amides, thiourea and their derivatives.
  • hydrophilic binder is a water soluble high molecular weight compound selected from the group consisting of gelatin. polyvinyl alcohol, polyvinyl pyrrolidone. casein. starch. carboxymethyl cellulose, gum arabic. said hydroxymethyl cellulose 20.
  • said hydrophilic binder is a water soluble high molecular weight compound selected from the group consisting of gelatin. polyvinyl alcohol, polyvinyl pyrrolidone, casein, starch, carboxymethyl cellulose, gum arabic. and hydroxymethyl cellulose.
  • said support member is a sheet material selected from the group consisting of papers. glasses. plastic films, and thin metal plates.
  • said support is a sheet material selected from the group consisting of papers, glasses, plastic films, and thin metal plates.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Heat Sensitive Colour Forming Recording (AREA)
  • Photosensitive Polymer And Photoresist Processing (AREA)
  • Thermal Transfer Or Thermal Recording In General (AREA)
US265887A 1971-06-23 1972-06-23 Sensitizing a granular dispersion of a n-vinyl compound and an organohalogeno compound by heat Expired - Lifetime US3876426A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4006021A (en) * 1971-04-20 1977-02-01 Fuji Photo Film Co., Ltd. Sensitizing a granular dispersion of a color generator and an organic halogen compound by heat

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3476562A (en) * 1963-05-06 1969-11-04 Bell & Howell Co Light sensitive composition comprising an organic amine and an organic halogen compound in a hydrophilic binder
US3510304A (en) * 1966-12-22 1970-05-05 Horizons Research Inc Dry working black image compositions comprising organic halogen compounds and ethylene compounds
US3607266A (en) * 1963-05-06 1971-09-21 Bell & Howell Co Image intensification process for sensitized film
US3649284A (en) * 1970-11-17 1972-03-14 Scott Paper Co Furfurvylidene-lower haloalkane photosensitive composition containing arylamino disulfide
US3697276A (en) * 1971-02-01 1972-10-10 Horizons Research Inc Polyvinylcarbazole photographic systems

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3476562A (en) * 1963-05-06 1969-11-04 Bell & Howell Co Light sensitive composition comprising an organic amine and an organic halogen compound in a hydrophilic binder
US3607266A (en) * 1963-05-06 1971-09-21 Bell & Howell Co Image intensification process for sensitized film
US3510304A (en) * 1966-12-22 1970-05-05 Horizons Research Inc Dry working black image compositions comprising organic halogen compounds and ethylene compounds
US3649284A (en) * 1970-11-17 1972-03-14 Scott Paper Co Furfurvylidene-lower haloalkane photosensitive composition containing arylamino disulfide
US3697276A (en) * 1971-02-01 1972-10-10 Horizons Research Inc Polyvinylcarbazole photographic systems

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4006021A (en) * 1971-04-20 1977-02-01 Fuji Photo Film Co., Ltd. Sensitizing a granular dispersion of a color generator and an organic halogen compound by heat

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GB1394875A (en) 1975-05-21
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